Automatic electric flatiron



March 26, 1929. M. c. BERSTED AUTOMATIC ELECTRIC FLATIRON Filed Feb. 14, 1927 2 Sheets-Sheet I N V EN TOR. Mew 6. 5595220 By M A TTORNEY March 26, 1929. M, B RSTED 1,707,042

AUTOMATIC ELECTRIC FLATIRON Filed Feb. 14, 1927 2 Sheets$heet 2 INVENTOR.

A T TORNEY Patented Mar. 26, 1929.

UNITED STATES MARTIN CJBERSTED, OF SAN DIEGO, CALIFORNIA.

AUTOMATIC ELECTRIC FLATIRON.

Application filed February 14, 1927. Serial No. 168,055.

My invention relates to automatic electric flat irons, and the objects of my invention are: first, to provide a particularly simple and economically constructed automatic elec- 5 tric fiat iron; second, to provide an iron of this class in which the thermostat member is not under strain except at the approximate point of separating contact; third, to provide an iron of this class having a spring actuated switch means in which the spring is located outside of the hot area and protected from the heat therein, the spring means bemg positioned in a compartment accessible by the atmosphere, thus keeping the spring means relatively cool and. considerably increasing the life thereof; fourth, to provide a novelly constructed flat iron of this class having an externally operated mechanism for controlling the temperature at which the thermostat will break contact, said heat control mechanism provided with a spring means for maintaining tension in which the spring means is located outside of the hot area and protected from the heat therein, the spring means being positioned in a compartment accessible by the atmosphere, thus keeping the spring relatively cool and considerably increasing the life. thereof; fifth,'to provide a novelly constructed casing for a flat iron of this class having a pair of backwardly extending hollow lugs for supporting the fiat iron on its end, the spring means for actuating the switch mechanism of the iron being positioned in one of said hollow lugs, and the spring means for actuating the heat control mechanism being positioned in the other ofsaid hollow lugs, and both springs separated therein from the intense heat of the body of the flat iron; sixth, to provide a novelly constructed means for regulating .the tension of the various springs used in this device; seventh, to provide a novelly constructed, compact unit for supporting the heat controlling andautomatically actuated switch mechanism, whereby said mechanism maybe easily mounted within the flat iron or easily replaced by other units; eighth, to

provide an automatic electric flat iron in which the heat controllable thermostat memher is placed in close proximity to the heating element of the iron so as to be readily responsive to thechanging of heatin the iron, thus increasing the etii'ciency" and accuracy thereof; ninth, to provide a novelly constructed, double. contact switch mechanism for an iron o f-' this class;'tenth, to provide means for adjusting the power of the thermostat relative to the contact supporting member; eleventh,-to provide as a whole a novelly constructed automatic flat iron, and twelfth, to provide an iron of this class which is very able, eflicient, and which will not readily deteriorate or get out of order.

With these and other objects in view, as will appear hereinafter, my invention consists of CQItEtlIIYDOVGl features of construction, combination and arrangement of parts and portions, as will be hereinafter described in detail and particularly set forth in the appended claims, reference being had to the accompanying drawings and to the characters of refereneethereon, which form a part of this application, in which:

Figure l is a side elevational viewof my automatic electric flat iron, showing the general'construction of the enclosed case; Fig. 2 is a sectional view thereof in plan, taken through 2-2 of Fig. 1; Fig. 3 is a frag mentary bottom view of the casing, with the base plate, heating element and upper plate removed and my thermostat mechanism in position thereon, showing the hollow extending lugs partially broken: away and in section to facilitate the illustration; Fig. 4 is a fragmentary rear elevational view of my flat iron, taken from the line 44 of Fig. 1; Fig.

5 is a longitudinal sectional view thereof,

through 5-5 of Fig. 2; Fig. 6 is a rear elevational view thereof, with the rear casing or supporting member and the base plate removed; Fig. 7 is a transverse sectional view thereof, through 7-7 of Fig. 1, showing the casing with the base plate heating element and upper plate removed and showing the thermostat support member in section and the thermostat mechanism in elevation, and. Fig. 8 is a fragmentary sectional view thereof, through 8-8 of Fig. 7

Similar characters of reference refer to similar parts and portions throughout the several views of the drawings.

The lower and heating portion of my electric flat iron, as illustrated in the drawings, and consisting of the base plate 1, insulating material 2 positioned thereon, the electric heating element 3 positioned between the insulating material, the upper plate 4 positioned above the insulating material and clamping the latter between the plates 1 and 4, and the screws 5 securing the above mem here together, is of the conventional construction.

The thermostat mechanism, the switch mechanism, and the heat controlled mechanism, are mounted as a complete unit on the support6. This support 6 is a T-shaped member or plate bent downwardly at its enlarged rear end, as indicated by 6. This downwardly extending portion 6 rests on the upper side of the rear end of the base plate 1. Said member 6 is also provided intermediate its ends with a pair of downwardly extending lugs 6*,which rest on the upper side of the upper plate 4 and form a channel portion between the same and the horizontal plat-e portion 6 of the member 6. The complete unit, mentioned above and supported on the member 6, is covered and encased by a casing 7, which rests at its lower edge on the upper side of the base plate 1. Between the under side of the casing 7 and the upper side of the support 6 extend the lower ends of the handle sup porting members 8 and 9, at the upper ends of which handle members is secured a suitable handle, 10. Through the upper side and substantially middle portion of the easing 7, the inner ends of the handle supporting members 8 and 9, and the plate portion 6" of the support 6, extends a single large screw 11, which is scrcwably secured at its inner end in the upper plate 4, as shown best in Fig. 5, thus simply but rigidly securing said members together.

Through the lower portion of the downwardly extending portion 6 of the support 6 extends a pair otbinding posts 12 and 13 in the form of bolts, which are insulated from the support 6. To the outwardly extended ends of said binding posts are secured the ends 3- and 3 of the heating element of the iron, which ends of the heating element extend outwardly through openings 6 at the lower end of the support 6, as shown best in Figs. and 6. The inner end of the binding post 12 is connected, by means of a conductor 14, with the terminal post 15. Said terminal post 15 and another, terminal post 16 are secured at their lower ends in and insulated from the support 6 and extend upwardTy therefrom through openings in the casing 7. Said terminal posts are protected at their outer ends b means of a terminal protecting member 1% extending around the same and secured to the handle supporting member 9.

At the inner side of the downwardly extending portion 6* of the support 6 is positioned a pair of spaced apart conductor plates 18 and 19, the former'o't which is secured in position by and electrically connected to the inner end of the terminal post 13. The other conductor plate 19 is similarly secured to the support 6 by means of a bolt 20 and is electrically connected, by means of an integral conductor 21, with the other terminal post 16. Said conductor iy, are mounted contact members 22 and 23, n

which are adapted to be simultaneously engaged and electrically connected by a switch bar 24, which is supported intermediate the ends of and insulated from the shiftable switch member or lever 25, which is pivotally mounted at its outer end in a forwardly extending lug (39 secured to the inner side of the downwardly extending portion of the support 6, as shown best in Figs. 3 and 7. The contact members 22 and 23, as well as the contacting switch bar 24, are preferably made of silver.

On the downwardly extending portion 6 of the support 6 and directly behind the pivotal switch lever 25 is mounted a hollow spring support 26,-which extends backwardly therefrom and supports at its extended end a compression spring 27. The outer end of the compression spring 27 is turned back, extending through the hollow support 26, and is pivotally connected at its forwardly extended end to and intermediate the ends of the switch lever 25, as shown best in Fig. 3, thus normally retaining the contacting switch bar 24 in engagement with the contact members 22 and 23. The hollow spring support is threaded on its external surface and adapted to be screwed in and out of the portion 6 of the member 6, thereby providing a means for adjusting the tension of the switch spring 27.

At the rear portion of the iron is positioned a casing and supporting member 28, which is secured, by means of screws 28 extending through the casing 7, to the downwardly extending portion 6 of the support 6. This member 28 is provided with a pair of hollow leg portions 28 for supporting the iron at its end when not using the same. In one of these hollow leg portion 28 extends the hollow support 26 and the compression spring 27, thus positioning the same without the area of intense heat of the iron and necessarily increasing the life of the spring. Through the lower wall of the member 28, forming the hollow legs 28 are provided vent holes 28 for admitting air to the 1101- low leg portions 28, thus facilitating the cooling of the spring. The member 28 encloses the whole rear portion of the iron, as shown best in Figs. 1, 2, 3, 4 and 5.

At the opposite end ofihe inner side of the downwardly extending portion 6 of the support 6 is provided another forwardly extending lub 6 on which is pivotally mounted one end of the thermostat member supporting lever 29, which extends toward the axial 'line of the iron. Near the pivotal end of ,the lever 29 and at the forward side thereof in the form of a bar and consists of two plates of metal of different coefficients of expansion. A lug protrudes from the free end of the switch lever 25 and is provided with an adjusting screw 25, which is adapted to engage the free end of the thermostat member 31 when the latter is distorted by heat, thus forcing the free end of the switch lever- 25 forwardly and simultaneously disengaging the contact or bar 24 from the contact members 22 and 23. The screw 25* is adjustable so that the maximum temperature of the iron may be regulated and made tamper-proof.

It will be here noted that with this construction and relation of the thermostat member 31 with the switch lever 25, the thermostat member is permitted to expand or contract, or distort freely, without mechanical resistance, until the heat of the iron becomes greater than the temperature at which it is set. Then the free end ,of the thermostat member engages the adjusting screw 25 of the switch lever. Thus, the life of the thermostat is materially increased.

On the downwardly extending portion 6 of the support 6 and directly behind the pivotal thermostatsupporting member 29 is a hollow spring support member 32, which extends backwardly therefrom and supports at its extended end a compression spring 33. The outer end of the compression spring 33 is turned back, extending throughthe hollow support 32, and is pivotally connected at its forwardly extended end to and intermediate the ends of the thermostat supporting member 29, as shown best in Fig. 3 of the drawings. The spring 33 tends to draw the thermostat supporting member 29 against a cam 34 and also tends to hold the thermostat supporting member 29 and the thermostat 31 away from the switch 25, but at the same time placing no mechanical strain upon the thermostat 31. The spring support member 32 and spring-33 are similar to the spring support 26 and spring 27, but are slightly larger and heavier in construction so as to best serve their functions. Similarly to the spring support 26, the spring support 32'is threaded on its external surface and is adapted to be screwed in and out of the portion 6 of the member 6, thereby providing means for adjusting the tension of the spring 33.

The cam 34 is revolubly mounted in the portion 6* of the member 6 at the median line thereof by means of a constricted shaft portion 34, which extends outwardly through the portion 6 and throu h the casing 28/ On'its rear or outer en is rigidly secured, by means of a screw 35, a circular plate or dial 36, which is provided with lug portions 36 formed by bending portions of the member 35 outwardly from its surface. The lugs 36 serve as ahandle for turning the dial member 36, thereby turning the cam 34. On the outer side of the member 28 are the letters L, M and H stamped thereon, which correspondto low, medium, and high'heats. On the plate 36 is a notch 36", which indicates which heat the iron is set for. To further facilitate the action of the cam, a collar 37 is positioned around the constricted shaft portion 34* between the member 28 and the portion. 6*.of the member 6. The cam isalso provided with a lug portion 34? on its inner or cam end. The lug 34 extends through a hole in the free end of the thermostat supporting lever 29 and retainsit in position on the cam.

When the plate or dial 36 is turned, the cam turns and moves the thermostat supporting member, thereby moving the thermostat 31 toward or away from the adjusting screw 25*. The further the thermostat member 31 is away from the adjusting screw 25", the hotter the iron will be before the thermostat will break thecircuit. Thus, the adjusting screw 25" serves to regulate the maximum temperature of the iron, and the dial 36, by means of the cam action of the cam 34, regulates the degree of heat desired for the various .uses of the iron. When the dial is set at L or low heat, the cam holds the thermostat in the closest position to the screw 25". At hot the cam allows the thermostat to be a greater distance from the screw 25. Any position between low and high heat holds the thermostat 6 a corresponding position between the low and high heat positions of the thermostat.

Though I have shown and described a particular construction, combination and arrangement of parts and portions, I do not wish to be limited to this particular construttion, combination and arrangement, but desire to include in the scope of my invention, the construction, combination and ar-' rangement substantially as set forth in the appended claims.

Having thus described my invention, what I claim as new and desire to secure. by Letters Patent is:

1. In a heat controlling means, a supporting means, 'a thermostatsupporting lever pivotally mounted on said supporting means, adjusting means for said lover, athermostat bar carried by said lever, a contact member mounted on said supporting means, a switch lever pivotally mounted on said supporting means, and another contact member carried by said switch lever, said thermostat bar and said switch lever being positioned in such a manner as to permit free movement of said thermostat bar when subjected to heat and to permit said contaet members to remain in engagement until said thermostat bar is distorted a predetermined distance.

2. In a heat controlling means, asupport, a thermostat supporting lever pivotally mounted at its one end on said support, a

thermostat member secured at its one end near the pivotal axis of said lever, a pair of contact members supported on and insulated from said support, and a switch lever pivotally mounted at its one end on said support and provided with a contact switch bar insulated therefrom and adapted to con nect said contact members, the free ends of said thermostat member and said switchlever being engageable in such a manner that the switch lever is not shifted about its pivotal axis until said thermostat member has been shifted a predetermined distance.

In a heat controlling means, a casing adapted to be subjected at one portion of its interior to a source of heat, a support mounted therein, /a thermostat supporting lever pivotally mounted at its one end on said support, a thermostat member secured at its one end near the pivotal axis of said lever, a pair of contactmembers supported on and insulated from said support, a switch lever pivotally mounted at its one end on said support and provided with a contact switch bar insulated therefrom and adapted to connect said contact members, the free ends of said thermostat member and said switch lever being engageable in such a manner that the switch lever is not shifted about 'its pivotal axis until said thermostat member has been shifted a predetermined distance, and a spring means mounted on said support and positioned outside of the area of the intense heat of the casing, the outer end of said spring means being connected to said switch lever for normally retaining the contact switch bar thereof in engagement with said contact members.

4. In a heat controlling means, a supporting means, a thermostat supporting lever pivotally mounted on said supporting means, adjusting means for said lever, a thermostat bar carried by said lever, a contact member mounted on said supporting means, a switch lever pivotally mounted on said supporting means, and another contact member carried by said switch lever, said thermostat bar and said switch lever being adjustably spaced in such a manner as to permit free movement of said thermostat bar when subjected to heat and to permit said contact members to remain in engagement until said thermostat bar is distorted a predetermined distance.

5. In a heat controlling means, a support,

a thermostat supporting lever pivotally mounted at its one end on said support, a thermostat member secured at its one end near the pivotal axis of said lever, a pair of contact members supported on and insulated from said support, a switch lever pivotally mounted at its one end on said support and provided with a contact switch bar insulated therefrom and adapted to connect said contact members, the free ends of said thermostat member and said switch lever being spaced in such a manner that the switch lever is not shifted about its pivotal axis until said thermostat member has been shifted a predetermined distance, and cam means for adjusting the position .of said thermostat.

6. In a heat controlling means, a casing adapted to be subjected at one portion of its interior to a source of heat, a support mounted therein, a thermostat supporting lever pivotally mounted at its one end on said support, a thermostat member secured at its one end near the pivotal axis of said lever, a pair of contact members supported on and insulated from said support, a switch lever pivotally mounted at its one end on said support and provided with a contact switch bar insulated therefrom and adapted to connectvsaid contact members, the free ends of said thermostat member and said switch lever being spaced in such. a manner that the switch lever is not shifted about its pivotal axis until said thermostat member has been shifted a predetermined distance, a spring means mounted on said support and positioned outside of the area of the intense heat of the casing, the outer'end of said spring means being connected to said switch lever for normally retaining the contact switch bar thereof in engagement with said contact members, and a resilient means connected to said thermostat supporting member tending to hold-said thermostat away from said switch lever.

7. In a heat controlling means, a support, a thermostat supporting lever pivotally mounted at its one end on said support, a thermostat member secured at its one end near the pivotal axis of said lever, a pair of contact members supported on and insulated from said support, a switch lever pivotally mounted at its one end on said support and provided with a contact switch bar insulated therefrom and adapted to connect ,said contact members, the free ends of said thermostat member and said switch lever being spaced in such a manner that the switch lever is not shifted about its pivotal axis until said thermostat member has been shifted a predetermined distance, and a resilient means connected to said thermostat supporting member tending to hold said thermostat away from said switch lever.

8. In an automatic electric flat iron, a circuit formed by a pair of terminal members. a heating element and a normally closed switch member, and an independent therznostat member adapted to be influenced by the heat of said heating element and to actuate said switch after certain free distortion of said thermostat .member.

9. In an automatic electric fiat iron, a cireuit formed by a pair of terminals, a heating element and a switch member, resilient means for normally closing said switch me111l1er and an independent thermostat 111e111l1er adapted to be ini'lueneed by the heat of said heating'elenmnt and to open said switch after certain free distortion of said thermostat member, and means for limiting the free distortion of said therm0- stat prior to actuating said switch member.

In testimony whereof, I have hereunto set my \hand at San Diago, California, this 5th day of February, 1927.

MARTIN C. BERS'F'EI), 

